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Mk 3 bonnet vents

PostPosted: Thu Jan 03, 2013 6:31 pm
by Moneypit
Hi all and a happy new year.
Can anybody help me out here?
I've been using the Midas as my daily commute for the past year now and haven't encountered this problem before.
Just before Christmas it was becoming a little difficult to start. Not firing when turning over but just trying as the ignition was switched off.
I thought it might be the coil, electronic ignition or even just a tired battery. Being too busy to look before now it's been laid up for the last month.
Now I've had a look and basically the air filter was full of water and quite a bit in the carb.
Should there be any sort of water diverter on the underside of the vents? I see others have had worries about the one over the battery but haven't seen the one above the carb mentioned.
I presume through trial these are deemed necessary and can't be blanked off because of overheating problems.

Many thanks

Dave

Re: Mk 3 bonnet vents

PostPosted: Thu Jan 03, 2013 6:49 pm
by Stuart
They didn't have any form of diverter as standard, they're not too bad for garaged cars, a complete no no for none standard air filters.
The extra vents were added to cater for turbo cars, earlier cars only had two vents, (the outer ones I think?)

Re: Mk 3 bonnet vents

PostPosted: Thu Jan 03, 2013 6:52 pm
by max midas
Can't say I've had a problem on my Mk. 3 with either the vents above the carb or the one above the battery.
But then we have had quite a bit of water falling on us in the UK these last few months! :roll:

Re: Mk 3 bonnet vents

PostPosted: Thu Jan 03, 2013 7:06 pm
by Moneypit
Thanks for the replies.
When I get chance,I'll get the carb off and dry it thoroughly. Not certain that any water has got past the needle, just presume it has.
Might turn out yet to be an electrical problem and this is just an added bonus.
Has anybody blanked the middle vents off running a standard 1275cc engine without any problems?

Re: Mk 3 bonnet vents

PostPosted: Thu Jan 03, 2013 7:18 pm
by Hans Efde
These vents were added to the bonnet because of vapour lock problems. They are not a bad thing to have. Perhaps you can make a splash shield for the airfilter. When I had my battery under the bonnet of my second coupe I made a rubber flap over it to prevent it getting wet via the outer vent. That's certainly a useless vent. But the ones in the middle are useful and blocking them may cause problems in the summer.

Re: Mk 3 bonnet vents

PostPosted: Thu Jan 03, 2013 8:16 pm
by Moneypit
I use to get vapour lock problems with an old Rover P6. If you stopped the engine and left it for about 20mins, no way would it start.Right royal pain in the proverbial, so I'll be leaving the vents open somehow.